The advent of high-bandwidth technologies, such as ADSL2+ and VDSL2, which can operate at frequencies up to 30 MHz, has enabled service providers to use their existing copper infrastructure to support new types of services, such as IPTV (Internet Protocol Television). Traditionally, service providers have used POTS (Plain Old Telephone Service) or telephony testing techniques to pre-qualify DSL (Digital Subscriber Line) subscribers or to troubleshoot problems on the copper wire. Generally, the basis of such testing techniques is on narrowband resistive or capacitive measurements. These measurements sufficed for basic internet applications, where service providers typically provisioned the subscriber line below the data rate capacity. The new high-bandwidth services, however, made the subscriber line increasingly susceptible to physical loop impairments and wideband noise disturbers. These impairments and disturbers can produce intermittent service or degrade picture quality. To offer advanced services, therefore, requires DSL testing and diagnostics that can ensure the subscriber lines are able to support the needed throughput, performance, and stability.